This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The use of viral vectors as carriers of therapeutic agents in the CNS is a field of great interest for the treatment of neurodegenerative diseases, most particularly for Parkinson's disease, because of the preferential loss of nigrostriatal dopaminergic neurons, and the fact that the currently used long term dopamine replacement therapy results in major side effects that considerably limit the use of such therapeutic approach in advanced patients. In the present project, Dr Smith has developed a research program supported by Oxford Biomedica in UK to determine the antiparkinsonian efficacy of a lentiviral vector transfected with the necessary enzymes and co-factor for dopamine synthesis (hereby called Prosavin), in the MPTP-treated nonhuman primate model of Parkinson's disease. A group of seven monkeys were rendered parkinsonian following chronic injections of the toxin MPTP before they received five injections of 10 microliters (ie a total of 50 microliters per structure) of the viral vector in the sensorimotor territory of the postcommissural putamen. Following the injections, animals were allowed to survive for a period of 3-6 months during which their behavior was monitored on a weekly basis to assess changes in their parkinsonian symptoms. Data obtained so far have indicated modest behavioral improvement in some, but not all monkeys that received the vector injections. Postmortem studies are in progress to assess the extent of striatal transfection and the resulting degree of striatal dopamine innervation. These findings in nonhuman primates will serve as the basic foundation for clinical trials in humans with Parkinson's disease.